CDA-2诱导胶质瘤细胞SWO-38分化并抑制其增殖的作用机制

目的:诱导分化是肿瘤治疗的新策略,CDA-2是1种高效低毒的新型细胞分化剂,本实验研究CDA-2对人脑胶质瘤细胞SWO-38诱导分化作用并探讨CDA-2诱导分化的机制。方法:应用MTT法检测CDA-2对SWO-38细胞活性的抑制作用、平板集落形成实验检测CDA-2对SWO-38细胞的增殖抑制作用、免疫组化检测SWO-38细胞GFAP的表达、Western blotting检测SWO-38细胞PPARγ、COX-2及GFAP蛋白的表达。结果:CDA-2能明显抑制人脑胶质瘤细胞SWO-38活性及增殖,其IC50值分别为(2.33±0.37)g·L-1及(0.51±0.01)g·L-1;3g·L-1CDA-2处理SWO-38细胞72h即表现为细胞突起增多变长,细胞高表达GFAP蛋白;同时CDA-2可诱导SWO-38细胞PPARγ表达上调和COX-2表达下调。结论:CDA-2对胶质瘤SWO-38细胞具有增殖抑制及诱导分化作用,其作用机制可能与GFAP、PPARγ和COX-2信号转导通路有关。

Glob-N对胶质瘤细胞株SWO-38生长的体外实验研究

目的 :为了探讨正常及肿瘤相关中性鞘糖脂 (N GSLs)对肿瘤细胞生长的调控作用。方法 :采用改良的Hakomori方法提取、纯化正常人脑、牛脑、正常人“O”型血红细胞膜的N GSLs ,运用柱层析的方法分离正常人脑、牛脑、红细胞膜的红细胞糖苷脂 (Glob N)及人脑二己糖神经鞘氨醇 (CDH) ,MTT法检测各种来源的Glob N及人脑CDH对胶质瘤细胞株SWO 38生长的影响。结果 :三种不同来源的Glob N均能抑制SWO 38细胞的增殖。其中以正常人脑的作用最强 ,红细胞来源的作用次之 ,牛脑来源的最弱 ,而人脑CDH则缺乏抑制作用。结论 :Glob N是一种胶质瘤细胞的生长抑制因子 。

人脑胶质瘤细胞SWO-38条件培养基对中脑神经元活性的影响及其活性物初步分离

目的 探讨人脑胶质瘤细胞SWO -38条件培养基 (SWO -38CM)对SD大鼠中脑神经元生物活性的影响并对活性物初步分离。 方法 制备SWO -38CM并超滤浓缩 ,将分子量大于10KD的SWO -38CM行SephacrylS-200-HR凝胶层析 ,用MTT分析法确定神经营养活性。结果 分子量大于10KD的SWO-38CM及其凝胶层析Ⅱ峰可提高MTT分析法的光密度值。结论 人脑胶质瘤细胞SWO -38可分泌促进中脑神经元活性的物质 ,该物质的分子量大于10KD。

人胶质瘤细胞SWO-38神经营养活性物的初步分离

制备了人胶质瘤细胞ＳＷＯ－３８条件培养基（ＳＷＯ－３８ ＣＭ），经超滤浓缩，截留分子量大于 １０ ｋＤ的 ＳＷＯ－３８ ＣＭ，并运用快速自动比色微量分析法检测其对体外培养的 ＳＤ大鼠小脑皮质神经元的作用．结果表明，分子量大于 １０ ｋＤ的 ＳＷＯ－３８ ＣＭ对神经元的作用，与对照组比较有明显的神经营养活性．分子量大于 １０ ｋＤ的 ＳＷＯ－３８ ＣＭ经 ＳｅｐｈａｃｒｙｌＳ－２００－ＨＲ凝胶层析并结合生物活性鉴定，获得了具有神经营养活性的第Ⅱ峰洗脱液．

噬菌体随机肽库中与神经胶质瘤细胞系SWO-38特异性靶向结合短肽的筛选

神经胶质瘤的常规治疗尚难取得令人满意的效果,寻找高效和高特异性杀伤肿瘤细胞的药物已成为提高其治愈率的研究热点。本研究旨在利用噬菌体随机肽库找到与神经胶质瘤细胞系SWO-38特异性结合并内化人细胞的短肽序列。方法:利用噬菌体随机12肽库对肿瘤细胞进行5轮全细胞筛选,分析筛选后单克隆对神经胶质瘤细胞的特异性结合能力并进行免疫荧光分析。提取单克隆DNA,测序,得出短肽序列进行比对分析。结果:通过5轮筛选后的噬菌体库及所挑选的表面及内化部分各13个单克隆均显示对胶质瘤细胞有较高的特异性结合,并测序得到三条重复性高的多肽序列。免疫荧光分析显示噬菌体大量聚集在细胞表面并能够内化进入到细胞内。结论:通过噬菌体随机肽库对肿瘤细胞进行全细胞筛选得到的噬菌体多肽能高特异性与胶质瘤瘤细胞SWO-38结合,可作为肿瘤导向药物研究的载体。

Antitumor effect of tumor necrosis factor-related apoptosis inducing ligand combined with mevastatin on a human glioma cell line SWO-38

BACKGROUND： Previous studies have reported that statins are less toxic to the human body and have greater antitumor activity; however, few studies have addressed the antitumor effect of statins combined with tumor necrosis factor-related apoptosis inducing ligand （TRAIL）. OBJECTIVE： To explore the effect of TRAIL combined with mevastatin on the proliferation and apoptotic cell death of a human glioma cell line SWO-38, and to study its mechanism of action. DESIGN, TIME AND SETTING： An in vitro control experiment was performed at the Central Laboratory of the Third Hospital Affiliated to Sun Yat-sen University, between January and April 2009. MATERIALS： The human SWO-38 cell line was provided by Cell Research, Department of Animal Experimental Center of Sun Yat-sen University; human recombinant soluble TRAIL by R＆D, USA; and mevastatin by Sigma, USA. METHODS： SWO-38 cells were separately incubated in TRAIL （100, 200, 300, 400, and 500 tJg/L） and mevastatin （5, 10, 20, 30, and 40 pmol/L） for 72 hours. In addition, SWO-38 cells were incubated in TRAIL （300 μg/L）, mevastatin （30 μmol/L）, and a solution containing both TRAIL and mevastatin for 12, 24, 48 and 72 hours. MAIN OUTCOME MEASURES： Cell proliferation was detected using methyl thiazolyl tetrazolium assay; cell apoptosis was observed using Hoechst 33258 staining and fluorescence microscopy and was measured using Annexin V/propidium iodide flow cytometry; TRAIL R1/DR4 and TRAIL R2/DR5 protein expressions levels were measured using indirect immunofluorescence staining combined with flow cytometry in the recombinant soluble TRAIL （rsTRAIL, 300 tJg/L）, mevastatin （30 IJmol/L） and combination groups; TRAIL R1/DR4 and TRAIL R2/DR5 mRNA expression was detected using real-time polymerase chain reaction. RESULTS： rsTRAIL, mevastatin and their combination inhibited tumor proliferation in a time- and dose-dependent manner. The proliferation inhibitory rate and apoptosis rate of human SWO-38 cells in the combined group were significantly greater than the rsTRAIL or mevastatin alone group （P 〈 0.01）. TRAIL R1/DR4 and TRAIL R2/DR5 protein and mRNA expressions were increased in the combination group compared with mevastatin or rsTRAIL alone after 72 hours （P 〈 0.01）. CONCLUSION： Both rsTRAIL and mevastatin inhibit the proliferation and apoptosis of the human glioma cell line SWO-38, while their combination enhances the anti-tumor effect. The mechanism of action possibly correlates to the upregulation of TRAIL R1/DR4 and TRAIL R2/DR5 mRNA expression by mevastatin, thereby enhancing the cell sensitivity to rsTRAIL.

CDA-Ⅱ诱导人胶质瘤细胞分化与抑瘤的作用

目的研究人尿萃取物CDA-Ⅱ(cell d ifferentiation a-gent-Ⅱ,又名尿多酸肽)对人胶质瘤细胞SWO-38抑制增殖及诱导分化作用。方法应用MTT法、集落形成试验检测CDA-Ⅱ对SWO-38细胞增殖的影响;通过光镜观察和免疫组化鉴定细胞分化;利用裸鼠抑瘤实验观察CDA-Ⅱ抗胶质瘤生长的作用。结果一定浓度的CDA-Ⅱ可使SWO-38细胞增殖与集落形成均明显受抑,并呈剂量依赖性。经1 g.L-1CDA-Ⅱ处理后,光镜观察发现SWO-38细胞胞体变大,核浆比减小,突起增多,表现出向成熟的星形细胞分化现象。免疫组化显示胶质纤维酸性蛋白(glial fibrillary ac id ic prote in,GFAP)表达增强。体内抑瘤试验见高、低剂量CDA-Ⅱ均可抑制裸鼠移植瘤生长,抑瘤率为79.94%、42.77%(P<0.05,n=10)。结论CDA-Ⅱ不仅能够抑制人胶质瘤SWO-38细胞的生长,而且能诱导SWO-38细胞分化,是一种很有应用前景的诱导分化剂。